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991.
992.
Laura Monti Ana Pontoriero Natalia Mosconi Cecilia Giulidori Estela Hure Patricia A. M. Williams María Victoria Rodríguez Gabriela Feresin Darío Campagnoli Marcela Rizzotto 《Biometals》2010,23(6):1015-1028
The reaction between phthalylsulfathiazole (H2PST), in alkaline aqueous solution, and cobalt(II) nitrate led to a pink solid, [Co(PST)(H2O)4] (1), which was characterized by elemental and thermogravimetric analysis; FT-IR, Raman and diffuse reflectance spectra. Spectroscopic
data reveal that the ligand would be doubly deprotonated and that the Co(II) ion environment is a distorted octahedral one.
(1) showed antibacterial activity similar to the ligand. 相似文献
993.
R Felicioli G Montagnoli S Monti J S Moore G O PHillips A Sosnowski 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1975,27(6):525-532
Pulse radiolysis and steady-state X-radiolysis have been used to investigate the radiation inactivation of aldolase from rabbit muscle. Both eaq-and OH readily react with aldolase, and contribute to inactivation. The radical anions (CNS)2-and (Br)2-react with aldolase at neutral pH. The progressive addition of alkali results in an increase in the second-order rate constants, with an apparent pK approximately 10 +/- 0-3, and with the formation of an unstable intermediate, lambdamax approximately 400 nm resembling a phenoxyl radical. Steady-state radiolysis in the presence of (CNS)2-and (Br)2- at alkaline pH results in increased aldolase inactivation, with a pK of enzyme inactivation similar to that observed for reaction of the radical anions. We propose that a reaction of the radical anoins with tyrosine residues accounts for the resultant inactivation. 相似文献
994.
Nitroxide TEMPOL impairs mitochondrial function and induces apoptosis in HL60 cells. 总被引:4,自引:0,他引:4
E Monti R Supino M Colleoni B Costa R Ravizza M B Gariboldi 《Journal of cellular biochemistry》2001,82(2):271-276
The piperidine nitroxide TEMPOL induces apoptosis in a number of tumor cell lines through free radical-dependent mechanisms. As mitochondria play a major role in apoptosis as both source and target for free radicals, the present study focuses on mitochondrial effects of TEMPOL in a human promyelocytic leukemic cell line (HL-60). On 24-h exposure to TEMPOL, the following alterations were observed: 1) decrease in both the intracellular and mitochondrial glutathione pools; 2) impairment of oxidative phosphorylation; and 3) decrease in mitochondrial membrane potential. In addition, TEMPOL was found to specifically target complex I of the respiratory chain, with minor effects on complexes II and IV, suggesting that mitochondrial effects might play a role in TEMPOL-induced oxidative stress and apoptosis, and that TEMPOL might sensitize tumor cells to the pro-apoptotic effects of cytotoxic agents. 相似文献
995.
Several different methods of analysis are applied to data consisting of weight measurements, taken at specified post-treatment times, of harvested thyroids from rats given one of four treatments. Previous studies of this type of data indicated that the growth is initially rapid, and that a second phase of less rapid growth is followed by a final phase in which little additional growth occurs. The data are further characterized by increasing variance through time. The primary purpose of the analysis is to study the effect of the treatments at the end of the study period. One-way analysis of variance tests among groups are performed on each day, but the results are not particularly helpful. However, results from two-way analyses of variance (over subsets of days and groups) are consistent with the three phase model and accordingly indicate significant group differences during each. Finally, maximum likelihood methods are used to fit a three part segmented linear regression model. 相似文献
996.
997.
Porcine trypsin (EC 3.4.4.4) converted, within approximately 2 hr at 50°C, its 1000-fold weight of water-insoluble, heat-denaturated cheese whey protein into a water-soluble product. In the course of this digestion, the enzyme increased the α-amino nitrogen of the protein by a factor of >20, from 0.40 to 9.40%. After digesting the water-insoluble whey protein, fully active trypsin could be recovered from the soluble digest with the aid of a cellulose-based affinity adsorbent. The enzyme which was eluted from a column of p-aminobenzamidine, bound to succinylated aminododecylcellulose, was fully active and showed essentially unchanged kinetic properties with a synthetic substrate, L -benzoyl-arginine p-nitroanilide. It was possible to perform, with the same amount of trypsin, three subsequent and equally effective solubilizations of whey protein, followed by a fourth digestion which still yielded a soluble product, but was considerably slower and incomplete. During each digestion, an estimated 30% of the trypsin was lost. The was not due to a decreased efficiency of the affinity adsorbent, as its trypsin-binding capacity was essentially unaffected after over 10 cycles of use. 相似文献
998.
999.
S. G. SUGUNA K. GOPALA RATHINAM A. R. RAJAVEL V. D HAN DA 《Medical and veterinary entomology》1994,8(1):88-94
Abstract. Anopheles subpictus Grassi is shown to comprise four reproductively distinct species, designated A, B, C and D, occurring sympatrically in villages of Pondicherry, southeast India.
Adult females were reared individually from wild larvae and examined for their morphological and chromosomal characters. Paracentric fixed inversions on the X-chromosome serve to distinguish the species cytogenetically, with no inversion heterozygotes (i.e. no interspecific hybrids) among totals of 717 species A (X+a ,+b ), 1863 species B (Xa, b), 869 species C (Xa,+b ) and 1365 species D (X +a ,b) identified.
Morphologically, diagnostic characters for each of the four species are seen in the egg float ridge number, larval mesothoracic seta 4, pupal seta 7-1 and the palpi of female adults. Species A. C and D immatures inhabit freshwater, whereas the malaria vector species B breeds in saltwater and was found only in coastal villages. 相似文献
Adult females were reared individually from wild larvae and examined for their morphological and chromosomal characters. Paracentric fixed inversions on the X-chromosome serve to distinguish the species cytogenetically, with no inversion heterozygotes (i.e. no interspecific hybrids) among totals of 717 species A (X+
Morphologically, diagnostic characters for each of the four species are seen in the egg float ridge number, larval mesothoracic seta 4, pupal seta 7-1 and the palpi of female adults. Species A. C and D immatures inhabit freshwater, whereas the malaria vector species B breeds in saltwater and was found only in coastal villages. 相似文献
1000.
Rita Del Giudice Alessandra Pesce Flora Cozzolino Maria Monti Annalisa Relini Renata Piccoli Angela Arciello Daria Maria Monti 《Biometals》2018,31(4):551-559
Specific mutations in APOA1 gene lead to systemic, hereditary amyloidoses. In ApoA-I related amyloidosis involving the heart, amyloid deposits are mainly constituted by the 93-residue N-terminal region of the protein, here indicated as [1-93]ApoA-I. Oxidative stress is known to be an enhancing factor for protein aggregation. In healthy conditions, humans are able to counteract the formation and the effects of oxidative molecules. However, aging and atmospheric pollution increase the concentration of oxidative agents, such as metal ions. As the main effect of iron deregulation is proposed to be an increase in oxidative stress, we analysed the effects of iron on [1-93]ApoA-I aggregation. By using different biochemical approaches, we demonstrated that Fe(II) is able to reduce the formation of [1-93]ApoA-I fibrillar species, probably by stabilizing its monomeric form, whereas Fe(III) shows a positive effect on polypeptide fibrillogenesis. We hypothesize that, in healthy conditions, Fe(III) is reduced by the organism to Fe(II), thus inhibiting amyloid formation, whereas during ageing such protective mechanisms decline, thus exposing the organism to higher oxidative stress levels, which are also related to an increase in Fe(III). This alteration could contribute to the pathogenesis of amyloidosis. 相似文献